Magnetic safety ski binding



Nov. 21, 1967 R. H. SOM MER MAGNETIC SAFETY SKI BINDING Filed Aug. 7, 1964 4 Sheets-Sheet l Nov. 21, 1967 R. H.- SOMMER 3,353,835

MAGNETIC SAFETY SKI BINDING Filed Au 7, 1964 4 Sheets-Sheet 2 FIG. 6

.lnvenfon Reinhold H. Sommor AGENT,

Nov. 21, 1967 R. H. SOMMER 3,353,835

MAGNETIC SAFETY SKI BINDING Filed Aug. 7, 1964 4 Sheets-Sheet 5 FIG. 9

L l 4 I! 2 :1

' hvemor:

Reinhold H. Sommar Nov. 21, 1967 H. SOMMER 3,353,835

MAGNETIC SAFETY SKI BINDING Filed Aug. 7, 1964 4 Sheets-Sheet 4 4 r I 5 F 27 I d 2 t I L9H Z 2% 28 2% bvenfon I 6U AGENT United States Patent O 3,353,835 MAGNETIC SAFETY SKI BINDING Reinhold H. Summer, Essen, Germany, assignor to Beteiligungsund Patentverwaltungsgesellschaft mit beschrankter Haftung, Essen, Germany, a corporation of Germany Filed Aug. 7, 1964, Ser. No. 388,199 Claims priority, application Germany, Aug. 16, 1963, B 73,141; June 12, 1964, B 77,218 12 Claims. (Cl. 280-1135) My present invention relates to a safety ski binding designed to release the boot of a skier from its supporting runner in response to unusual stresses, such as those occurring in the event of a fall.

Conventional safety ski bindings rely on spring pressure for the biasing of heel and/or toe clamps adapted to yield when the spring pressure is overcome by an external force, the clamps being usually adjustable to compensate for a fatiguing of the springs. The necessary bias is then maintained with the aid of screw connections which, however, are liable to spontaneous loosening so that an un timely release of the binding may occur. Furthermore, the clamps once loosened can be reset only by hand, thus requiring a skier who has kept his stance to bend down in order to retighten them.

The general object of my invention, therefore, is to provide an improved safety ski binding avoiding the aforestated disadvantages.

This object is redized, pursuant to the instant invention, by the provision of a ski binding which dispenses with all conventional spring clamps and utilizes, instead, at least one pair of retaining elements of which one is a permanent magnet and the other a ferromagnetic armature, the two elements being so positioned and arranged as to prevent the detachment of the boot from the runner in the absence of a force of unusual magnitude exceeding the force of attraction effective between these elements. Thus, I may respectively mount the two elements on the two members which are to be releasably interconnected, i.e. the runner and the boot, and/or I may incorporate them in a boot-engaging toe or heel clamp which is hingedly secured to the runner in a manner known per se and which is normally prevented by the retaining elements from swinging out of a boot-engaging position.

The two retaining elements need not be mounted directly on the boot and the runner, but the upper element may be secured to the boot by way of a special holder or attachment (e.g. a removable heel clip) whereas the lower element rests on a supporting plate which may be rigidly connected with the runner or resiliently hinged thereto at the front of the boot. The two elements or their carriers may be provided with interfitting formations to prevent relative lateral displacement; thus, for example, the aforementioned holder and plate may be formed with complementary longitudinal corrugations in a region offset from the location of the magnetic pair or pairs secured thereto, though alternatively or supplementally it is possible to provide one of the paired elements with a projection (e.g. a ball or a pin) receivable in a depression of the other element. One element, preferably the magnet, may also be received in a somewhat deeper recess accommodating the associated other element, namely the armature, to prevent them from shifting sideways relatively to each other in their contacting position. In order to give the binding a certain resiliency in response to minor impacts, the elements or at least one of them may be cushioned by resilient pads interposed between them and their supporting members, with one or both elements projecting from their supports to maintain a limited and variable clearance between the boot 3,353,835 Patented Nov. 21, 1967 and the runner. Particularly the upper element, if cushioned in this manner, may be received in a downwardly open recess of the boot or its attachment and may be cemented onto the walls of this recess by a deformable potting material.

A particularly stable arrangement according to the invention includes a toe clamp, which could be of the aforedescribed magnetically loaded type, releasably engaging the front of the boot whereas a heel attachment projects rearwardly beyond the boot and carries the magnet or armature element on its projecting part. The cooperating element could then be carried on a similarly projecting supporting plate or tongue which, particularly for cross-country skiing, may be of the above-mentioned resiliently hinged type enabling elastic lifting of the heel of the boot. In this case, i.e. with the magnetic unit disposed behind the boot, the two elements may be conveniently so disposed that their contact surfaces extend generally vertically rather than horizontally.

The invention will be described in greater detail with reference to the accompanying drawing in which:

FIG. 1 is a side-elevational view of a boot and runner provided with an improved safety ski binding according to the invention;

FIG. 2 is a cross-sectional view taken on the line II-II of FIG. 1;

FIG. 3 is a detail view on the line III-III of FIG. 2;

FIG. 4 is a view similar to FIG. 2, illustrating a modification;

FIG. 5 is a cross-sectional view of the embodiment of FIG. 4 taken in a plane parallel to that of the latter fi FIG. 6 is a view similar to FIG. 1, illustrating a further embodiment;

FIG. 7 is a cross-sectional view taken on the line VII-VI I of FIG. 6;

FIGS. 8, 9, l0 and 11 are still other elevational views similar to FIG. 1, illustrating yet further modifications;

FIG. 12 is an enlarged fragmentary elevational view illustrating a partial modification of the arrangement of FIG. ll; and

FIG. 13 is a top plan view of the assembly of FIG. 12.

The safety ski binding shown in FIGS. 1-3, serving to attach a boot 3 to a runner 1, comprises three longitudinally spaced pairs of magnetic units each including a permanent magnet 2 and an associated soft-iron armature 8. The permanent magnet element 2 of each unit is here shown to project slightly from a recess in runner 1, the corresponding armature 8 being imbedded in a holder 4 attached to the boot and being flush with the underside of that holder. The means for attaching the holder 4 to the boot 3 include a set of flexible straps 7 passing through upstanding lugs 6 on the sides of the generally plate-shaped holder whose front end is bent at 5 around the toe portion of the boot. Screws 9, 9" secure a pair of cross-bars 10', 10" to therunner 1 so as to form two transverse ridges abutting the toe and'heel portions, respectively, of the boot.

As illustrated in FIGS. 2 and 3, the elements 2 may each consist of an annular magnet 2' surrounding a softiron core 2" which is integral with a surrounding softiron housing 2". This construction may be used also in any one of the embodiments described hereinafter even though it has not been illustrated in subsequent figures.

With the arrangement shown in FIG. 1 it is possible, upon the occurrence of severe stresses overcoming the adhesive force of the magnetic units, to detach the entire boot 3 from the runner 1 or, say, to lift only its toe or heel portion momentarily. It is also possible to tilt the boot laterally with reference to the runner whereby the armatures 8 are lifted off the associated magnets 2 along only one side of the runner while remaining close to these magnets along the other side, thus preventing complete detachment of the boot from the runner. While the abutments 10-" block longitudinal shifting between the runner and the boot, lateral displacement may be prevented by similar external abutments or by some of the means described hereinafter.

In FIGS. 4 and 5 the magnets 2h have been elevated above the runner 1 with interposition of a supporting plate 11 which, in regions between the pairs of magnetic units 2h, 8, has corrugated extensions with longitudinal crests 11 and troughs 11" interfitting with similar crestsand troughs 4c, 40" of corrugated extensions of a modified holder 4c attached to the boot. The magnets 211 and the supporting plates 11 are attached to the runner 1 by screws 12. It will be apparent that the corrugations 11, 11" and 4c, 40, extending over the full width of the runner 1, prevent a relative lateral displacement of the boot (not shown in FIGS. 4 and 5) and the runner as long as the armatures 8 rest on their magnets 2h.

In FIG. 6 I have shown a toe clamp 4a which is hinged to the runner 1, forwardly of the boot 3, by eyelets 13 so as to be swingable about a horizontal axis. Such swinging is normally prevented by a magnetic unit 2a, 8a, the magnet 2a of that unit being fixedly secured to clamp 4a whereas the armature 8a is rigid with runner 1. A similar unit 211, 8b is disposed rearwardly of the boot, the magnet 211 being rigid with the runner 1 whereas its armature 8b is carried on a rearwardly projecting part of a heel attachment 4!). As best seen in FIG. 7, the heel of boot 3 has lateral ribs 14, e.g. of metal or plastic, fitting into grooves 15 of the yoke-shaped heel attachment or clip 4b which is thus removably engaged with boot 3. It will be evident that, as long as armature 8b is firmly attracted by magnet 2b, heel clip 417 will not become disengaged from the boot unless the toe clamp 4a opens under excessive stress to allow the boot to swing upwardly and/ or slide forwardly on the runner. The swinga-ble toe clamp4a is, of course, representative of a variety of magnetically loaded clamps adapted to engage either the front portion or some other part of the boot. As in the previous embodiments, several units 2a, 8a or 2b, 812 may be disposed side by side.

In FIG. 8, where a toe clamp 4a is fixedly secured to the runner 1 with the aid of screws 16 (only one shown), the magnet (which again may be one of a pair) is shown received in a downwardly open recess at the heel of boot 3, this recess being deep enough to accommodate the co-operating armature 8c, fastened to runner 1, when the boot rests firmly on the runner. As a supplemental means for preventing relative horizontal shifting between the runner and the boot, I have shown a ball 17 partly irnbedded in magnet 20 and projecting into a corresponding depression 19 in the surface of armature 80. In FIG. 9, by way of modification, I have shown a reversal of the magnetic unit with its magnet 2d recessed in runner 1 and its armature 8d mounted on the heel of the boot; a locator pin 18 rises from magnet 2d and enters a bore 20 in armature 8d.

FIG. 10 shows a heel clip 4b which is generally similar to the attachment 4]; of FIGS. 6 and 7 but has a downwardly open recess to accommodate a magnet 2e. An elactic cushion 21, such as a rubber pad, overlies the magnet 2e within its recess while a similar cushion 22 underlies the associated armature 8e which is partly recessed in runner 1. A peripheral space remaining within the recess of attachment 4b around magnet 2e is filled with an elastically deformable potting agent 23, e.g. a polyurethane, this arrangement affording some relative mobility to boot 3 and runner 1 in view of the fact that one of the two elements, here the armature 8e, projects from the member on which it is carried. Such elastic mounting of either or both elements of a magnetic unit may, of course, also be used with other embodiments herein disclosed. The cementing action of the potting agent 23 is supplemented by a fastening screw 12a which tightly holds the magnet 2e against the pad 21.

In FIG. 11 I have shown a boot-supporting plate or tongue 24 resiliently hinged to the runner ll, the front portion 24 of this tongue being attached to the runner by screws 25 While its rear portion 24 is resiliently defiectable to permit a limited raising of the heel of boot 3. Portion 24 has fixed to its rearwardly projecting extremity a 'boss 26 to which a permanent magnet 2g is attached in an upright position; the corresponding armature 8g is secured to a bracket 4d attached to the heel of boot 3. It will be noted that the two elements 2g, 8g have a generally vertical contact surface enabling the heel of the boot to detach itself from the boss 26, in response to unusual stresses, whereupon the front of the boot will slip out from under the toe clamp 4a" fixedly mounted on tongue 24.

As shown in FIGS. 12 and 13, the unitary resilient plate 24 may be replaced by a rigid tongue 24a and a rigid anchor plate 24b interconnected by a coil spring 27 which is wound under tension about a hinge pin 28, the two extremities 27, 27" of the spring bearing respectively upon plates 24b and 24a so as to resist a lifting of the boot heel. Front plate 24b is secured to runner 1 by screws 25a.

The resiliently hinged tongues 24 and 24a may be immobilized with reference to the runner 1 by suitable latch means, e.g. as illustrated in FIG. 11 where a latch 29 is slidable on runner 1 for insertion into a bore 3% of boss 26.

It will be apparent that various features individually described with reference to specific embodiments are mutually compatible so as to be readily combinable with one another, these and other modifications well understood by persons skilled in the art being intended to be embraced within the spirit and scope of my invention as defined in the appended claims.

I claim:

1. A safety ski binding for releasably mounting a boot on a runner, comprising an attachment secured to said boot, a first retaining element on said attachment, a co operating second retaining element on said runner, one of said elements being permanently magnetic, the other of said elements being a ferromagnetic armature attractable by said magnetic element, and a support on said runner underlying said second element and rigid therewith, said attachment and said support being plate-shaped in the region of said elements and being integrally provided with complementarily longitudinally corrugated extensions beyond said region preventing relative lateral displacement of said attachment and support, said extensions overlying the runner over substantially its full width.

2. A safety ski binding for releasably mounting a boot on a runner, comprising a first retaining element on said boot and a co-operating second retaining element on said runner, one of said elements being permanently magnetic, the other of said elements being a ferromagnetic armature attractable by said one element, said binding further comprising a boot-supporting plate resiliently hinged to the runner at the front of the boot, said first element being mounted at the heel of the boot, said second element being carried on the rear end of said plate.

3. A safety ski binding for releasably mounting a boot member on a runner member, comprising at least one permanent-magnet element carried on one of said members, at least one ferromagnetic armature element carried on the other of said members for co-operation with said magnet element, at least one of said elements projecting from the surface of its carrier member toward the other element whereby a limited clearance is maintained between said members upon contact between said elements, and resilient pad means interposed between at least one of said elements and its carrier member for enabling variation of said clearance.

4. A ski binding as defined in claim 3 wherein the lastmentioned element is received in a recess of its carrier member with lateral spacing from the wall of said recess, said means being a cushioning layer in said recess, further comprising fastening means for holding said lastmentioned element in said recess with limited mobility, said fastening means including a deformable potting material in the space adjoining said wall.

5. A safety ski binding for releasably mounting a boot member on a runner member, comprising at least one permanent-magnet element carried on one of said members, at least one ferromagnetic armature element carried on the other of said members for co-operation with said magnet element, at least one of said elements projecting from the surface of its carrier member toward the other element whereby a limited clearance is maintained between said members upon contact between said elements, and a pair of resilient cushions interposed between said elements and their respective carrier members for enabling variation of said clearance.

6. A ski binding as defined in claim 5 wherein the upper one of said elements is received in a recess of said boot member with lateral spacing from the wall of said recess, further comprising fastening means for holding said upper element in said recess with limited mobility, said fastening means including a deformable potting material in the space adjoining said wall.

7. A safety ski binding for releasably mounting a boot member on a runner member, comprising at least one permanent-magnet element on one of said members, at least one ferromagnetic armature element mounted on the other of said members for co-operation with said magnet element, and a toe clamp on said runner member releasably engageable with the front portion of said boot member, said toe clamp being provided with hinge means securing it to said runner member with freedom of swinging about a horizontal axis forwardly of said boot member, further comprising an additional permanent magnet mounted on said toe clamp rearwarly of said hinge means and a co-operating additional ferromagnetic armature mounted on said runner member underneath said additional magnet for holding said toe clamp against a swinging about said axis.

8. A safety ski binding for releasably mounting a boot on a runner, said boot being provided with a heel attachment having a part projecting rearwardly beyond the heel of the boot, comprising a first retaining element secured to said rearwardly projecting part, a co-operating second retaining element mounted on said runner, one of said elements being permanently magnetic, the other of said elements being a ferromagnetic armature attractable by said magnetic element, and a toe clamp on said runner releasably engageable with the front portion of said boot, said element engaging each other behind said boot along a generally vertical contact surface, said runner being provided with a support for said second element extending rearwardly beyond said heel attachment.

9. A ski binding as defined in claim 8 wherein said support is a plate resiliently hinged to said runner forwardly of said toe clamp and biased to raise the heel of said boot, said toe clamp being mounted on said plate.

10. A safety ski binding for releasably mounting a boot on a runner, comprising fixed abutment means on said runner bearing endwise upon said boot, and permanent-magnet retaining means including a pair of co-operating ferromagnetic elements disposed, respectively, on said runner and on the underside of said boot for exerting a magnetic force which normally prevents escapement of the boot from said abutment means in the absence of stress between said boot and said runner exceeding said magnetic force.

11. A ski binding as defined in claim 10 wherein said abutment means comprises a toe clamp forwardly of said retaining means.

12. A ski binding as defined in claim 11 wherein said abutment means further comprises a heel-engaging stop rearwardly of said retaining means.

References Cited UNITED STATES PATENTS 2,276,826 3/ 1942 Crowther 280-11.35 2,806,396 9/1957 Miller 317-159 X 2,884,698 5/1959 Wursch 317-159 X 3,023,017 2/ 1962 Landry 280l1.35 3,111,728 11/1963 Alderfer 317-159 X 3,165,328 1/ 1965 Malone 28011.35 3,246,907 4/ 1966 Chisholm 28011.35

FOREIGN PATENTS 61,783 10/ 1913 Austria. 192,308 10/ 1957 Austria. 206,751 12/ 1939 Switzerland. 252,152 9/ 1948 Switzerland.

BENJAMIN HERSH, Primary Examiner.

MILTON L. SMITH, Examiner. 

10. A SAFETY SKI BINDING FOR RELEASABLY MOUNTING A BOOT ON A RUNNER, COMPRISING FIXED ABUTMENT MEANS ON SAID RUNNER BEARING ENDWISE UPON SAID BOOT, AND PERMANENT-MAGNET RETAINING MEANS INCLUDING A PAIR OF CO-OPERATING FERROMAGNETIC ELEMENTS DISPOSED, REPSECTIVELY, ON SAID RUNNER AND ON THE UNDERSIDE OF SAID BOOT FOR EXERTING A MAGNETIC FORCE WHICH NORMALLY PREVENTS ESCAPEMENT OF THE BOOT FROM SAID ABUTMENT MEANS IN THE ABSENCE OF STRESS BETWEEM SAID BOOT AND SAID RUNNER EXCEEDING SAID MAGNETIC FORCE. 